College of Food Science and Engineering, Northwest A&F University, Yangling 712100, China.
College of Food Science and Engineering, Northwest A&F University, Yangling 712100, China; Shaanxi Engineering Research Centre of Dairy Products Quality, Safety and Health, Yangling, Shaanxi 712100, China.
Int J Food Microbiol. 2024 Dec 2;425:110885. doi: 10.1016/j.ijfoodmicro.2024.110885. Epub 2024 Aug 20.
Cronobacter sakazakii is an opportunistic pathogen known for causing severe diseases. Mild heat treatment is commonly used in food processing, however, the pathogenic characteristics and underlying mechanisms of Cronobacter sakazakii strains remain poorly understood. In this study, we found that mild heat stress (MHS) at 52 °C can induce several deleterious effects in Cronobacter sakazakii, including damage to the cell wall, genomic DNA breakage, and misfolding of cytoplasmic proteins. These conditions lead to a decreased survival ability under acid, desiccation, and osmotic stress; a reduction in biofilm formation; and diminished motility. Notably, surviving C. sakazakii cells retain their pathogenicity, causing significant intestinal damage in newborn mice. This damage is characterized by epithelial sloughing and disruption of the intestinal structure. Tandem mass tag (TMT)-based proteomics identified 736 proteins with differential abundance across C. sakazakii strains subjected to mild heat stress, highlighting adaptations in biofilm formation, motility, and stress tolerance. Key regulatory changes were observed in phospholipid metabolism and protein synthesis, which underpin this complex stress response. This data illustrates a sophisticated balance between environmental adaptability and pathogenic potential. The metabolic and pathogenic responses of C. sakazakii to mild heat stress are closely linked to its phospholipid metabolism and the production of secretory proteins, both crucial for its virulence and reliant on membrane transport. This complex interplay emphasizes the need to understand these mechanisms to develop effective control strategies.
阪崎克罗诺杆菌是一种机会致病菌，可导致严重疾病。在食品加工中通常采用轻度热加工处理，然而，阪崎克罗诺杆菌菌株的致病特征和潜在机制仍了解甚少。在本研究中，我们发现 52°C 的轻度热应激（MHS）可在阪崎克罗诺杆菌中诱导多种有害影响，包括细胞壁损伤、基因组 DNA 断裂和细胞质蛋白错误折叠。这些条件导致其在酸性、干燥和渗透压胁迫下的生存能力下降，生物膜形成减少，运动能力减弱。值得注意的是，存活的阪崎克罗诺杆菌细胞保留其致病性，导致新生小鼠肠道严重损伤。这种损伤的特征是上皮细胞脱落和肠道结构破坏。串联质量标签（TMT）-基于蛋白质组学鉴定了 736 种在轻度热应激下阪崎克罗诺杆菌菌株中丰度差异的蛋白质，突出了生物膜形成、运动性和应激耐受性的适应性变化。在磷脂代谢和蛋白质合成中观察到关键的调控变化，这为这种复杂的应激反应提供了支持。这些数据说明了阪崎克罗诺杆菌在环境适应性和致病潜力之间的一种复杂平衡。阪崎克罗诺杆菌对轻度热应激的代谢和致病反应与其磷脂代谢和分泌蛋白的产生密切相关，这两者对其毒力至关重要，并且依赖于膜转运。这种复杂的相互作用强调了需要了解这些机制，以制定有效的控制策略。
